Black in Chinese Medicine

In Chinese medicine, black — and dark, dusky or greyish shades generally — is the colour of the Water element and the Kidney. A dark, dull complexion and shadowed circles under the eyes point to Kidney deficiency, while dark clots, a purplish tongue and a very dark complexion can indicate cold or blood stasis. Black is echoed in the dark herbs that tonify the Kidney and nourish Blood and essence, and in the black foods traditionally eaten to strengthen the Kidney. Because a very dark colour can also signal serious conditions, some dark signs need urgent medical attention. This page is part of the guide to colours in Chinese medicine.

On this page

What black and dark colours signify
A dark complexion and under-eye shadows
Dark tongue, urine and clots
The Water element and the Kidney
Black Chinese herbs
Black foods in Chinese food therapy
When dark signs need a doctor
Frequently asked questions

1. What black and dark colours signify

In Chinese medicine “black” covers the whole range of dark, dusky, greyish and dark-blue shades. It carries several linked meanings:

Kidney deficiency — a dark, dull, lustreless complexion, especially beneath the eyes, is the classic sign of a depleted Kidney.
Cold — dark colours are associated with the cold, deep, inward nature of the Water element.
Blood stasis — dark or purplish colours (of the tongue, lips or clots) indicate that Blood is not moving freely.
Severity — a very dark colour often reflects a long-standing or serious condition.

2. A dark complexion and under-eye shadows

A dark, dull complexion that lacks lustre is a classic sign of Kidney deficiency, often with tiredness, lower back weakness and a feeling of being cold. Dark circles or shadows under the eyes are the most familiar everyday example — in Chinese medicine the area beneath the eyes relates to the Kidney, so persistent dark shadows suggest Kidney depletion, often from overwork, insufficient rest or chronic strain. A dull, greyish, dark complexion can also accompany long-standing blood stasis.

3. Dark tongue, urine and clots

Tongue body — a purplish or bluish tongue indicates blood stasis or internal cold. A truly dark or black tongue is an extreme sign — of either extreme cold or extreme heat — and is significant.
Menstrual blood — dark, clotted menstrual blood suggests cold and blood stasis.
Urine — very dark urine usually reflects heat or concentration (including simple dehydration).
Stool — a black, tarry stool is a medical warning sign and needs urgent assessment (see below).

4. The Water element and the Kidney

Black is the colour of the Water element, whose organs are the Kidney and Bladder. Water governs the body's deepest reserves — the essence (Jing) that determines constitution, development, reproduction and ageing — and the balance of fluids. Its season is winter, its climate is cold, its taste is salty, and its emotion is fear. Because the Kidney is the root of the body's Yin and Yang, dark signs of Kidney depletion are taken seriously and treated with deep, nourishing methods.

5. Black Chinese herbs

Many dark, near-black herbs tonify the Kidney and nourish Blood and essence:

Shu Di Huang (prepared rehmannia) — a dense, black, sticky herb that richly tonifies Kidney and Liver, nourishes Blood and replenishes essence.
He Shou Wu — tonifies the Kidney and Blood and is traditionally linked with keeping the hair dark.
Han Lian Cao — nourishes Kidney and Liver Yin; its juice blackens on drying.
Hei Zhi Ma (black sesame) — nourishes Blood and essence and moistens; “hei” means black.

Others include Xuan Shen and Sang Shen (mulberry). As always, herbs are prescribed in a matched formula by a qualified practitioner.

6. Black foods in Chinese food therapy

“Black foods nourish the Kidney” is one of the best-known sayings in Chinese food therapy. Everyday black and dark foods used to support the Kidney include black beans, black sesame seeds, black rice, black (wood ear) fungus, seaweed and kelp, chestnuts and walnuts. They are especially valued in winter, the season of the Water element, when the Kidney is the focus of care.

7. When dark signs need a doctor

Some dark colours are important medical warning signs. A black, tarry stool can indicate bleeding in the upper digestive tract and needs urgent medical assessment. Blue or grey lips, tongue or fingertips (cyanosis) suggest the blood is short of oxygen and require emergency care. A new, dark, changing or irregular skin mole or patch should be checked by your doctor. Chinese medicine's understanding of dark colours as Kidney or blood-stasis patterns applies to constitutional signs — not to these acute warning signs, which must be diagnosed conventionally.

8. Frequently asked questions

What does black or a dark colour mean in Chinese medicine?

Black and dark, dusky or greyish shades are the colours of the Water element and the Kidney. A dark, dull complexion and shadowed under-eye circles point to Kidney deficiency, dark or purplish colours point to blood stasis, and dark colours are also associated with cold. A very dark colour often reflects a long-standing or serious condition.

What do dark circles under the eyes mean in Chinese medicine?

In Chinese medicine the area beneath the eyes relates to the Kidney, so persistent dark circles or shadows suggest Kidney depletion, often from overwork, insufficient rest, chronic strain or ageing. They can also accompany long-standing blood stasis. Addressing rest, sleep and the underlying Kidney pattern is the traditional approach.

Which Chinese herbs are black and what do they do?

Many dark, near-black herbs tonify the Kidney and nourish Blood and essence. Shu Di Huang (prepared rehmannia) richly tonifies the Kidney and Liver and nourishes Blood, He Shou Wu tonifies the Kidney and Blood and is linked with keeping hair dark, Han Lian Cao nourishes Kidney and Liver Yin, and Hei Zhi Ma (black sesame) nourishes Blood and essence and moistens.

What do black foods do in Chinese medicine?

Black foods are traditionally said to nourish the Kidney, a well-known principle in Chinese food therapy. Examples include black beans, black sesame, black rice, black wood ear fungus, seaweed, chestnuts and walnuts. They are especially valued in winter, the season of the Water element and the Kidney.

Are dark stools or a very dark tongue serious?

They can be. A black, tarry stool can indicate bleeding in the upper digestive tract and needs urgent medical assessment, and blue or grey lips, tongue or fingertips suggest the blood is short of oxygen and require emergency care. While Chinese medicine reads a dark tongue as extreme cold or heat and dark colours as Kidney or blood-stasis patterns, these acute signs must be diagnosed conventionally.